When using tokens and setting the survey to send confirmation emails, no confirmation email is sent if the related token had a uses_left value of >1 which after submit gets decreased to a value >0.

This might be related to the fact that no completion date is set after submit.

Steps To Reproduce

1. At any test survey activate tokens. Check that confirmation emails are activated
2. Add a new token with uses_left = e.g. 10
3. Activate the survey and use the new token to fill it out.
4. Uses left gets decreased but no confirmation email is being sent.